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s390: raise minimum supported machine generation to z10

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Machine generations up to z9 (released in May 2006) have been officially
out of service for several years now (z9 end of service - January 31, 2019).
No distributions build kernels supporting those old machine generations
anymore, except Debian, which seems to pick the oldest supported
generation. The team supporting Debian on s390 has been notified about
the change.

Raising minimum supported machine generation to z10 helps to reduce
maintenance cost and effectively remove code, which is not getting
enough testing coverage due to lack of older hardware and distributions
support. Besides that this unblocks some optimization opportunities and
allows to use wider instruction set in asm files for future features
implementation. Due to this change spectre mitigation and usercopy
implementations could be drastically simplified and many newer instructions
could be converted from ".insn" encoding to instruction names.

Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
This commit is contained in:
Vasily Gorbik
2022-02-24 22:43:31 +01:00
parent 432b1cc78e
commit 4efd417f29
23 changed files with 38 additions and 435 deletions
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22
arch/s390/kernel/processor.c
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@@ -172,8 +172,7 @@ static void show_cpu_summary(struct seq_file *m, void *v)
static int __init setup_hwcaps(void)
{
/* instructions named N3, "backported" to esa-mode */
if (test_facility(0))
elf_hwcap |= HWCAP_ESAN3;
elf_hwcap |= HWCAP_ESAN3;
/* z/Architecture mode active */
elf_hwcap |= HWCAP_ZARCH;
@@ -191,8 +190,7 @@ static int __init setup_hwcaps(void)
elf_hwcap |= HWCAP_LDISP;
/* extended-immediate */
if (test_facility(21))
elf_hwcap |= HWCAP_EIMM;
elf_hwcap |= HWCAP_EIMM;
/* extended-translation facility 3 enhancement */
if (test_facility(22) && test_facility(30))
@@ -262,21 +260,7 @@ static int __init setup_elf_platform(void)
get_cpu_id(&cpu_id);
add_device_randomness(&cpu_id, sizeof(cpu_id));
switch (cpu_id.machine) {
case 0x2064:
case 0x2066:
default: /* Use "z900" as default for 64 bit kernels. */
strcpy(elf_platform, "z900");
break;
case 0x2084:
case 0x2086:
strcpy(elf_platform, "z990");
break;
case 0x2094:
case 0x2096:
strcpy(elf_platform, "z9-109");
break;
case 0x2097:
case 0x2098:
default: /* Use "z10" as default. */
strcpy(elf_platform, "z10");
break;
case 0x2817: